New research reveals that queen bumblebees can breathe while fully submerged for up to a week, a critical adaptation for surviving flooded overwintering burrows. The discovery, published in Proceedings of the Royal Society B, highlights an overlooked aspect of insect hibernation: resilience to waterlogging.
The Unexpected Discovery
The ability came to light almost by accident. Researcher Sabrina Rondeau, while studying pesticide effects on bumblebees at the University of Guelph, found that several queens accidentally submerged in water-filled tubes survived—and continued to live normally. This prompted further investigation into how the insects managed to remain alive underwater for extended periods.
Why This Matters
Queen bumblebees enter a hibernation-like state called diapause for six to nine months each year. During this time, they nest in shallow underground burrows, which are prone to flooding from rain or snowmelt. Without the ability to survive underwater, these queens would drown before spring, preventing them from establishing new colonies. This adaptation is therefore essential for their survival and the continuation of bumblebee populations.
How They Breathe Underwater
The study does not yet explain the exact mechanism, but it suggests queens either significantly reduce their metabolic rate or extract oxygen from water in a way previously unknown in insects. Erin Treanore, a biologist at Duke Farms, notes that previous research focused on cold and dry conditions during diapause, but this is among the first studies to demonstrate bumblebees’ resistance to flooding.
“This is remarkable,” Dr. Treanore says. “It’s a crucial adaptation that allows these queens to survive conditions that would kill many other hibernating insects.”
The finding underscores the complexity of insect survival strategies and raises questions about how other species cope with extreme environmental changes. Understanding these adaptations is increasingly vital as climate change leads to more frequent and severe weather events, including flooding.
In conclusion, the underwater survival of bumblebee queens is a remarkable feat of natural adaptation. This discovery emphasizes that even in well-studied organisms, there are still fundamental survival mechanisms waiting to be uncovered.
